WaterQ

City Water Quality Rankings in California

601 cities ranked by drinking water quality.

Popular city water quality comparisons

Trending Cities

#385
Imperial
County, CA
92 A
#386
La Palma
County, CA
92 A
#387
Lake Almanor
County, CA
92 A
#388
Lodi
County, CA
92 A
#389
Long Beach
County, CA
92 A
#390
Montara
County, CA
92 A
#391
Oak View
County, CA
92 A
#392
Ojai
County, CA
92 A
#393
Palm Springs
County, CA
92 A
#394
Placentia
County, CA
92 A
#395
Rancho Cucamonga
County, CA
92 A
#396
Rancho Murieta
County, CA
92 A
#397
Riverbank
County, CA
92 A
#398
Rowland Heights
County, CA
92 A
#399
San Andreas
County, CA
92 A
#400
San Bernardino
County, CA
92 A
#401
Santa Barbara
County, CA
92 A
#402
Santa Cruz
County, CA
92 A
#403
Sonora
County, CA
92 A
#404
Springville
County, CA
92 A
#405
Sunnyvale
County, CA
92 A
#406
Anderson
County, CA
91 A
#407
Camp Pendleton
County, CA
91 A
#408
Cloverdale
County, CA
91 A

Frequently Asked Questions

How are city water quality rankings calculated in California?

WaterQ city rankings are based on EPA SDWIS data across local public water systems, including contaminant detections, compliance violations, and recency-weighted score signals.

Can I compare two cities in California?

Yes. Use the city comparison links on this page or open the Compare tool to evaluate two cities side by side on score, grade, and water system coverage.

How often does WaterQ refresh city data?

City-level metrics refresh when new EPA data is processed. Check city pages for latest score and violation context.

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